More than half of all human cancers contain a mutant gene that encodes a mutant protein known as Ras. In cancer cells, Ras activates the cells to divide in an unrestrained manner. To induce cell division, Ras must be localized at the inner surface of the cancer cell membrane. Membrane localization of Ras is effected by attachment of a hydrophobic group, typically the farnesyl group, which becomes attached to Ras. In some cells, the related geranylgeranyl group becomes attached instead. Both of these groups become attached to Ras enzymatically, in a process known as prenylation. Thus, interference with prenylation of Ras has the potential to prevent Ras localization at the inner surface of the cancer cell membrane, resulting in the cessation of unrestrained cell division of the cancer cell.
The enzyme that attaches the farnesyl group to Ras protein to facilitate the latter's localization at the inner surface of the cancer cell membrane is farnesyl protein transferase, also known as protein farnesyltransferase (herein referred to as FTase). The farnesyl group becomes attached to Ras by reaction with farnesyl diphosphate, also known as farnesyl pyrophosphate (herein referred to as FPP). In other words, FTase catalyzes the following reaction, in which Ras becomes attached to the farnesyl group by displacement of pyrophosphate (P2O74−, herein referred to as PPi):

The newly formed farnesyl-Ras localizes at the inner surface of the cancer cell membrane and causes the cancer cell to divide without restraint.
There is a continuing need in the art for new ways to inhibit the growth of cancer cells. There is a need in the art for new ways to inactivate targets which are specifically involved in cancer progression and development.